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comparison libtomcrypt/src/modes/lrw/lrw_process.c @ 1471:6dba84798cd5

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Update to libtomcrypt 1.18.1, merged with Dropbear changes
author Matt Johnston <matt@ucc.asn.au>
date Fri, 09 Feb 2018 21:44:05 +0800
parents f849a5ca2efc
children
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1470:8bba51a55704 1471:6dba84798cd5
3 * LibTomCrypt is a library that provides various cryptographic 3 * LibTomCrypt is a library that provides various cryptographic
4 * algorithms in a highly modular and flexible manner. 4 * algorithms in a highly modular and flexible manner.
5 * 5 *
6 * The library is free for all purposes without any express 6 * The library is free for all purposes without any express
7 * guarantee it works. 7 * guarantee it works.
8 *
9 * Tom St Denis, [email protected], http://libtom.org
10 */ 8 */
11 #include "tomcrypt.h" 9 #include "tomcrypt.h"
12 10
13 /** 11 /**
14 @file lrw_process.c 12 @file lrw_process.c
28 */ 26 */
29 int lrw_process(const unsigned char *pt, unsigned char *ct, unsigned long len, int mode, symmetric_LRW *lrw) 27 int lrw_process(const unsigned char *pt, unsigned char *ct, unsigned long len, int mode, symmetric_LRW *lrw)
30 { 28 {
31 unsigned char prod[16]; 29 unsigned char prod[16];
32 int x, err; 30 int x, err;
33 #ifdef LRW_TABLES 31 #ifdef LTC_LRW_TABLES
34 int y; 32 int y;
35 #endif 33 #endif
36 34
37 LTC_ARGCHK(pt != NULL); 35 LTC_ARGCHK(pt != NULL);
38 LTC_ARGCHK(ct != NULL); 36 LTC_ARGCHK(ct != NULL);
47 XMEMCPY(prod, lrw->pad, 16); 45 XMEMCPY(prod, lrw->pad, 16);
48 46
49 /* increment IV */ 47 /* increment IV */
50 for (x = 15; x >= 0; x--) { 48 for (x = 15; x >= 0; x--) {
51 lrw->IV[x] = (lrw->IV[x] + 1) & 255; 49 lrw->IV[x] = (lrw->IV[x] + 1) & 255;
52 if (lrw->IV[x]) { 50 if (lrw->IV[x]) {
53 break; 51 break;
54 } 52 }
55 } 53 }
56 54
57 /* update pad */ 55 /* update pad */
58 #ifdef LRW_TABLES 56 #ifdef LTC_LRW_TABLES
59 /* for each byte changed we undo it's affect on the pad then add the new product */ 57 /* for each byte changed we undo it's affect on the pad then add the new product */
60 for (; x < 16; x++) { 58 for (; x < 16; x++) {
61 #ifdef LTC_FAST 59 #ifdef LTC_FAST
62 for (y = 0; y < 16; y += sizeof(LTC_FAST_TYPE)) { 60 for (y = 0; y < 16; y += sizeof(LTC_FAST_TYPE)) {
63 *((LTC_FAST_TYPE *)(lrw->pad + y)) ^= *((LTC_FAST_TYPE *)(&lrw->PC[x][lrw->IV[x]][y])) ^ *((LTC_FAST_TYPE *)(&lrw->PC[x][(lrw->IV[x]-1)&255][y])); 61 *(LTC_FAST_TYPE_PTR_CAST(lrw->pad + y)) ^= *(LTC_FAST_TYPE_PTR_CAST(&lrw->PC[x][lrw->IV[x]][y])) ^ *(LTC_FAST_TYPE_PTR_CAST(&lrw->PC[x][(lrw->IV[x]-1)&255][y]));
64 } 62 }
65 #else 63 #else
66 for (y = 0; y < 16; y++) { 64 for (y = 0; y < 16; y++) {
67 lrw->pad[y] ^= lrw->PC[x][lrw->IV[x]][y] ^ lrw->PC[x][(lrw->IV[x]-1)&255][y]; 65 lrw->pad[y] ^= lrw->PC[x][lrw->IV[x]][y] ^ lrw->PC[x][(lrw->IV[x]-1)&255][y];
68 } 66 }
73 #endif 71 #endif
74 72
75 /* xor prod */ 73 /* xor prod */
76 #ifdef LTC_FAST 74 #ifdef LTC_FAST
77 for (x = 0; x < 16; x += sizeof(LTC_FAST_TYPE)) { 75 for (x = 0; x < 16; x += sizeof(LTC_FAST_TYPE)) {
78 *((LTC_FAST_TYPE *)(ct + x)) = *((LTC_FAST_TYPE *)(pt + x)) ^ *((LTC_FAST_TYPE *)(prod + x)); 76 *(LTC_FAST_TYPE_PTR_CAST(ct + x)) = *(LTC_FAST_TYPE_PTR_CAST(pt + x)) ^ *(LTC_FAST_TYPE_PTR_CAST(prod + x));
79 } 77 }
80 #else 78 #else
81 for (x = 0; x < 16; x++) { 79 for (x = 0; x < 16; x++) {
82 ct[x] = pt[x] ^ prod[x]; 80 ct[x] = pt[x] ^ prod[x];
83 } 81 }
90 } 88 }
91 } else { 89 } else {
92 if ((err = cipher_descriptor[lrw->cipher].ecb_decrypt(ct, ct, &lrw->key)) != CRYPT_OK) { 90 if ((err = cipher_descriptor[lrw->cipher].ecb_decrypt(ct, ct, &lrw->key)) != CRYPT_OK) {
93 return err; 91 return err;
94 } 92 }
95 } 93 }
96 94
97 /* xor prod */ 95 /* xor prod */
98 #ifdef LTC_FAST 96 #ifdef LTC_FAST
99 for (x = 0; x < 16; x += sizeof(LTC_FAST_TYPE)) { 97 for (x = 0; x < 16; x += sizeof(LTC_FAST_TYPE)) {
100 *((LTC_FAST_TYPE *)(ct + x)) = *((LTC_FAST_TYPE *)(ct + x)) ^ *((LTC_FAST_TYPE *)(prod + x)); 98 *(LTC_FAST_TYPE_PTR_CAST(ct + x)) = *(LTC_FAST_TYPE_PTR_CAST(ct + x)) ^ *(LTC_FAST_TYPE_PTR_CAST(prod + x));
101 } 99 }
102 #else 100 #else
103 for (x = 0; x < 16; x++) { 101 for (x = 0; x < 16; x++) {
104 ct[x] = ct[x] ^ prod[x]; 102 ct[x] = ct[x] ^ prod[x];
105 } 103 }
106 #endif 104 #endif
107 105
108 /* move to next */ 106 /* move to next */
109 pt += 16; 107 pt += 16;
110 ct += 16; 108 ct += 16;
111 len -= 16; 109 len -= 16;
112 } 110 }
113 111
114 return CRYPT_OK; 112 return CRYPT_OK;
115 } 113 }
116 114
117 #endif 115 #endif
118 /* $Source$ */ 116 /* ref: $Format:%D$ */
119 /* $Revision$ */ 117 /* git commit: $Format:%H$ */
120 /* $Date$ */ 118 /* commit time: $Format:%ai$ */